Electromagnetic drive mechanisms are suitable for a variety of short stroke, fast response applications. For example, a drive mechanism may be used to drive a bypass passage door for a high speed sorting device.
FIG. 1 illustrates an example of a conventional electromagnetic drive mechanism 1. Drive mechanism 1 may comprise a stator 2 and a rotor 3 that rotates relative to stator 2. Rotor 3 may comprise an output shaft 4 comprised of a non-magnetic material, and a rotor core 5 comprising a magnetic material and fixed to the output shaft 4. The rotor core 5 may comprise a plurality of rotor poles 6 of substantially uniform thickness.
The stator 2 may comprise a plurality of upper and lower stator core portions 7 comprised of a magnetic material and arranged along the axis of the rotor shaft 4, as well as winding groups 8 wrapped around the outside of stator core portions 7. The upper and lower stator core portions 7 comprise a plurality of stator pole 9. There may be a gap between rotor poles 6 and stator poles 9, allowing the rotor 3 to rotate relative to the stator 2.
While historically, performance, life cycle capability, heat transfer, hysteresis and curve profile have been the primary considerations when designing drive mechanisms, as systems and application evolve, other characteristics such as speed, responsiveness, and device size have increased in importance.
Thus, there exists a need for an improved compact, fast-response drive mechanism.